Choline supplementation in classic homocystinuria: impact on homocysteine and hepatic steatosis.

Background: Classic homocystinuria is a sulfur metabolism disorder caused by cystathionine beta synthase (CBS) deficiency. The primary aim of treatment is to maintain plasma homocysteine (Hcy) concentration within the target range. This study investigated choline status and the effect of choline supplementation in CBS-deficient homocystinuria patients with elevated Hcy levels despite standard therapy.

Methods: Fifteen CBS-deficient homocystinuria patients and 20 controls with normal Hcy levels were enrolled. The study group received 1000 mg/day of choline bitartrate for 8 weeks. The control group was not given any supplements. Anthropometric measurements, biochemical tests, liver magnetic resonance proton density fat fraction imaging, and food consumption records of the participants in the study group were evaluated at baseline and at the end of the study.

Results: All participants demonstrated inadequate dietary choline intake. Choline supplementation significantly increased plasma free and total choline levels (p < 0.01) and reduced average plasma Hcy levels from 123.1 ± 52.2 to 61.1 ± 42.9 µmol/L (p < 0.01). In three of the four patients with hepatic steatosis at the beginning of the study, the condition regressed with choline supplementation.

Conclusion: In conclusion, choline supplementation should be considered in CBS-deficient homocystinuria patients with low plasma choline and high Hcy levels despite standard therapy.

Impact: Choline supplementation further decreases plasma homocysteine levels in patients with classic homocystinuria who still have elevated plasma homocysteine levels on standard therapy. Choline supplementation led to a remarkable surge in plasma free and total choline levels, which marked a significant breakthrough for classic homocystinuria patients. Remarkably, choline supplementation reversed hepatic steatosis in three out of four patients, highlighting its powerful therapeutic potential.